Hello all, I am new here and just got referred to this site for some help.

I have noticed that she has a lot of torn finnage which I had always cured for her and the 3 other bettas she's with by using API Melafix. She is also pale and I can't say she is swimming as actively as her sisters. In fact, I can't even locate her now because I think she's hiding in her colosseum but she did come out of no where to feed when I opened the hatch just a few minutes ago. This morning I saw her with her body attached to the filter because it had pulled her in until I disconnected it for her.
this is her http://i.imgur.com/lcBDa.jpg another http://i.imgur.com/cHiTq.jpg
this is what shes supposed to look like http://i.imgur.com/czqDU.jpg
I am running the filter you see in the picture because it has the most bacteria until I feel comfortable running the aqua clear 20 alone that you can't see in the pics. It has been running for about 2 months but the biobag doesn't look too dirty so I am not sure if it's ready yet. nitrates and ammonia show as zero, later I'm going to test nitrites Everyone is well but her and the tank is about 4 months old.

She has been breathing heavily from what i can see and is mainly finding places in the tank to rest on even odd places like on top of the colosseum which I have never seen before.

Looks like fin rot I am guessing, should I QT her? I would need a step by step process of meds to use and items to put in the tanks if this is necessary.

Can provide any other info that may be needed to help me out, I know my post might not have all the info you guys would need to help me--it's a 10 gal with 4 bettas and 3 otos with aqua clear 20 and the basic aqueon filter that comes with the 10 gal. Everyone is at 100% except her

Well she was swimming by it this morning and got her right fin caught into it, I shut that filter off and it's still off right now just in case so my aqua clear 20 is running. I don't think she is ready to die by far. She is just a few months old and ate well earlier today when she came up for food, I also haven't noticed any of the bettas being aggressive to each other in a manner that would cause this.

Put her in a QT tank away from the others. Add in 1 tsp/gallon premixed Aquarium Salt and IAL or washed dried oak leaves to provide essential tannins. Keep the water level in QT low and make sure to not stress her, cover the tank with a blanket. Any meds with -fix can harm their labyrinth so you don't want that... Shaina, let's try to stay positive, we don't want to make the OP have a panic attack.

The treatment I suggested will help with Fin Rot and any external problems. So if this isn't Fin Rot, it won't hurt since it will help her fins heal and keep her strong. Give her high protein foods such as mosquito larvae to help tissue growth. Good Luck and maybe you should baffle your filter.

Or you could get a small Kritter Keeper. You just want a cheap tank that's more horizontal. The vertical space will be hard for her. Lights will be stressful, keep her in the warmest room. Remember the thermometer. Just dechlorinated water with dissolved AS will do. It doesn't really matter unless there is ammonia in the water. A hiding place will provide some cover.